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Hi, I'm trying to get into C++ and I was wondering about the class and method names.
I'm hailing from C#, where everything is written fully and all names are immediately comprehensible.
However, it seems in C++ mostly abbreviations are being used. Is there any good reason for this or is that just because C++ has been around since long before Intellisense, so it's just a matter of convenience?
Thanks.
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ya! it's only a matter of convenience to avoid long variable names and distinguishing them from being local or member variables. for example there is oneHungarian Notation[^] that can be followed. If you feel that the people who follow you, should understand the code by just having a glimpse at it, it would be better to use a notation. on an ending note - > If you use your own:DOCUMENT IT VERY CAREFULLY.
Somethings seem HARD to do, until we know how to do them.
 _AnShUmAn_
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It's not specific to C++. Different projects use different naming conventions, so depending on whose code you look at it will vary greatly. It's really a matter of preference. The C++ standard library comes all in one single namespace called std that deals with basic stuff like string manipulation, lists etc., whereas the .NET API pretty much wraps the entire OS API. The C++ library can get away with much shorter names since its feature set is very limited and defined, whereas .NET needs means to organize all that stuff, and it does so by using tons of nested namespaces, which results in much longer symbol names overall.
I agree that most STL class names are not necessarily immediatly comprehensible and are thus not really a good example to follow in terms of naming conventions. Nor are the MFC, which were conceived before design patterns, templates, and namespaces had reached the real world, plus they are massively influenced by the Windows API naming conventions and are overall much closer to a C library than to a modern C++ library.
My advice is to be as verbose as you need to be but as short as you can be without sacrificing clarity. The time you save when you use cryptic abbreviations is far less than the time it is going to cost when someone has to fix a bug in that code, or even just understand what it does.
If you want an example of what readable C++ code with good coding conventions and modern design looks like, check out the open source FreeCloth project. Reading through that code really changed the way I had been thinking about a few things.
Hope this helps,
Peter
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Hi,
I've got this problem and I can't solve it - I either have to rescale the image or somehow make the printer use page size equal to the image size - it should be able to do so, it's a virtual printer and not constrained by real paper sizes.
I think that using SetMapMode on the printer HDC can make it fit into the page size (like an implicit rescaling) but I don't know how to do it.
So is there any way to avoid this clipping? Any help would be greatly appreciated.
Here is the code I use (it makes clipped images):
ULONG_PTR m_gdiplusToken;
Gdiplus::GdiplusStartupInput gdiplusStartupInput;
Gdiplus::GdiplusStartup(&m_gdiplusToken, &gdiplusStartupInput, NULL);
Image* img = Image::FromFile(wstrFileName);
HDC hPrinterDC;
hPrinterDC = CreateDC("WINSPOOL\0", szVirtPrn, NULL, NULL);
if (hPrinterDC)
{
DOCINFO di = {0};
memset( &di, 0, sizeof(DOCINFO) );
di.cbSize = sizeof(DOCINFO);
di.lpszDocName = "DocName";
di.lpszOutput = (LPTSTR) NULL;
di.lpszDatatype = (LPTSTR) NULL;
di.fwType = 0;
int nResult = StartDoc(hPrinterDC, &di);
if (nResult > 0)
{
nResult = StartPage(hPrinterDC);
if (nResult > 0)
{
Graphics* g = Graphics::FromHDC(hPrinterDC);
g->DrawImage(img, 0, 0);
nResult = EndPage(hPrinterDC);
}
}
nResult = EndDoc(hPrinterDC);
DeleteDC(hPrinterDC);
}
There is sufficient light for those who desire to see, and there is sufficient darkness for those of a contrary disposition.
Blaise Pascal
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sashoalm wrote: g->DrawImage(img, 0, 0);
This will draw the image from 0,0 to actual image size. May be you want to use some other version of DrawImage() where you can specify destination rectangle. I hope it makes sense.
Regards,
Sandip.
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I'm trying to avoid any rescaling done with GDI+ because it might affect image quality.
Anyway I've come to a partial solution. This code
SIZE paper_size = { GetDeviceCaps(hPrinterDC, HORZRES), GetDeviceCaps(hPrinterDC, VERTRES) };
SIZE image_size = { img->GetWidth(), img->GetHeight() };
SetMapMode(hPrinterDC, MM_ANISOTROPIC);
SetWindowExtEx(hPrinterDC, image_size.cx, image_size.cy, NULL);
SetViewportExtEx(hPrinterDC, paper_size.cx, paper_size.cy, NULL);
SetWindowOrgEx(hPrinterDC, 0, 0, NULL);
seems to make it fit the page, but it doesn't preserve aspect ration. I did it with some sample code and trial and error.
There is sufficient light for those who desire to see, and there is sufficient darkness for those of a contrary disposition.
Blaise Pascal
modified on Tuesday, August 5, 2008 5:34 AM
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If
sashoalm wrote: SIZE paper_size = { GetDeviceCaps(hPrinterDC, HORZRES), GetDeviceCaps(hPrinterDC, VERTRES) };
Is less than
sashoalm wrote: SIZE image_size = { img->GetWidth(), img->GetHeight() };
You are going to rescale your image anyway. So what you trying to achieve may be i am not following your problem properly.
Regards,
Sandip.
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SandipG wrote: You are going to rescale your image anyway. So what you trying to achieve may be i am not following your problem properly.
Yes, i was saying that it's an alternative solution to what you suggested. this code is there to make the rescaling instead of calling GDI+ functions. but it doesn't preserve aspect ratio, so there's more to be done here...
There is sufficient light for those who desire to see, and there is sufficient darkness for those of a contrary disposition.
Blaise Pascal
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sashoalm wrote: but it doesn't preserve aspect ratio, so there's more to be done here...
For all these issues i think you should try GDI+ rescaling and check the quality. If you still dont want to use GDI+ resampling then there are some good articles on CP regarding it. Here is one by great CPallini http://www.codeproject.com/KB/GDI/plain_c_resampling_dll.aspx[^]
Regards,
Sandip.
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Hello Friends.
I want to made an exe file in c++/MFC that reads from an autorun.inf file. Now if the format of autorun.inf is ASCII, then it can't be read correctly by our exe. if its format is unicode, then it displays the correct information.
Now generally the format of autorun.inf/autorun.ini is ASCII. My problem is that i want to convert the format of "autorun.inf" from ASCII to Unicode manually. i search for this on different forums but i can't get any help.
Can any body help me. I shall be very thankful to all of You.
Thanx in Advance. 
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Since you say you want to do it manually, you could just open it in notepad and then SaveAs (choosing Unicode).
Hope that helps.
Karl - WK5M
PP-ASEL-IA (N43CS)
PGP Key: 0xDB02E193
PGP Key Fingerprint: 8F06 5A2E 2735 892B 821C 871A 0411 94EA DB02 E193
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Thanks a lot dear friend for your reply.
But i want to ask you one question i.s. what is notepad, and where can i find it?
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From the Start menu (Windows), choose Run, then type in "notepad" (without the quotes) and press return.
You can also find an enhanced version by using google to search for Notepad++.
Hope that helps.
Karl - WK5M
PP-ASEL-IA (N43CS)
PGP Key: 0xDB02E193
PGP Key Fingerprint: 8F06 5A2E 2735 892B 821C 871A 0411 94EA DB02 E193
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Hi all,
I am working on TFTP server application.
When A client is requested for a file, My OnReceive() function is called.
In the OnReceive(),I am unable to get the data requested. I used the function like
CListenSocket::OnReceive(int nErrorCode)
{
char buff[100];
memset(buff,0,sizeof(buff));
CAsyncSocket::OnReceive(nErrorCode);
if (nErrorCode)
{
Message.Format("OnReceive nErrorCode: %i", nErrorCode);
AfxMessageBox(Message);
return;
}
int Size = ReceiveFrom(buff, 100,IPAddress,Port);
}
Here I am able to get the IPAddress and Port correctly.
But Unable to get data in the buff variable.But Size value is not zero.
So what could be the problem?
Please help me.
Regards,
Sunil Kumar
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Make sure that the value returned by the function "ReceiveFrom" is a positive number less than 100.
Remember that the buffer ( buff[100]) you used to receive the data is sitting in the stack and will go out of scope when the function returns.
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Yeah I have checked the value itis returned. it is less than 100 only and Im checking the
buffer just after the Receivefrom function.i.e it is not out of the scope.
Regards,
Sunil Kumar
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CListenSocket::OnReceive(int nErrorCode)
{
char buff[100];
memset(buff,0,sizeof(buff));
if (nErrorCode)
{
Message.Format("OnReceive nErrorCode: %i", nErrorCode);
AfxMessageBox(Message);
return;
}
int Size = ReceiveFrom(buff, 100,IPAddress,Port);
CAsyncSocket::OnReceive(nErrorCode);
}
Just try this way.
-@SuDhIrKuMaR@-
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Thanks for the reply,
but still there is no data in buff.
I think atleast it must have the filename I am requesting from tftp client.!
Regards,
Sunil Kumar
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Why you are using ReciveFrom not Revice?
-@SuDhIrKuMaR@-
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I need to know the host address and port.
Even i tried receive() but no use.
Regards,
Sunil Kumar
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First, there's no need to call CAsyncSocket::OnReceive().
It does nothing.
If Size is > 0, then you received a datagram. If the data you expect
isn't in the datagram, you need to look at the sender to see why.
Mark
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://www.codeproject.com/script/Forums/Images/coffee.gif)
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I am getting the compiler error :
"error C2440: '=' : cannot convert from 'LPWSTR' to 'LPCSTR'"
and error line is
cmi.lpVerb = MAKEINTRESOURCE (uiCommand);
And my Code is :
CMINVOKECOMMANDINFO cmi;
ZeroMemory(&cmi, sizeof(CMINVOKECOMMANDINFO));
cmi.cbSize = sizeof(CMINVOKECOMMANDINFO);
cmi.fMask = CMIC_MASK_FLAG_NO_UI;
cmi.hwnd = m_hWnd;
cmi.lpParameters = NULL;
cmi.lpDirectory = NULL;
cmi.lpVerb = MAKEINTRESOURCE (uiCommand);
cmi.nShow = SW_SHOWNORMAL;
cmi.dwHotKey = NULL;
cmi.hIcon = NULL;
hr = pCtxMenu->InvokeCommand(&cmi);
How to do it?
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In the Project Settings, Select Configuration Properties->General->Character Set. Set this value to "Use Multi-Byte Character Set".
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